File Crawler

The File Crawler starts crawling in the rootFolder and produces one record for each subdirectory in the bucket connected to directoriesToCrawl (and each record goes to an own bulk), and one record per file in the folder in bucket connected to filesToCrawl (a new bulk is started each 1000 files). The bucket in slot directoriesToCrawl should be connected to the input slot of the File Crawler so that the subdirectories are crawled in followup tasks. The file records do not yet contain the file content but only metadata attributes:

fileName

fileFolder

filePath (also set as record ID)

fileExtension

fileSize

fileLastModified (also written to attribute _deltaHash for delta checking)

The attribute _source is set from the task parameter dataSource which has no further meaning currently, but it is needed by the delta service.

If the runnning CompoundExtractor service identifies an object as a extractable compound, it is marked with attribute _isCompound set to true.

The fileCrawler is usually the first worker in the workflow and the job is started in runOnce mode.

File Fetcher

Worker name: fileCrawler

Parameters: none

Input slots:

filesToFetch

Output slots:

files

For each input record, reads the file referenced in attribute filePath and adds the content as attachment fileContent

File Extractor Worker

For each input record, an input stream to the described file is created and fed into the CompoundExtractor service. The produced records are converted to look like records produced by the file crawler, with these attributes set (if provided by the extractor):

filePath: complete path in compound

fileFolder: folder of element in compound

fileName: filename part of path

fileExtension: extension part of filename

fileLastModified: last modification timestamp

fileSize: uncompressed size

_deltaHash: computed as by the FileCrawler worker

_compoundRecordId: record ID of top-level compound this element was extracted from

_isCompound: set to true for elements that are compounds themselves.

_compoundPath: sequence of filePath attribute values of the compound objects needed to navigate to the compound element.

If the element is not a compound itself, its content is added as attachment fileContent.